. >>> on the hill, david petraeus under heavy cover tells congress about the attack in benghazi, what he knew, when he knew it and why the u.s. first told the world what it did. >>> and 18 days since the devastation on the east coast. >>> and it is the end of the line for a guilty pleasure in america. but how did it come to this? nightly news begins now. >>> good evening, it worries them enough that israel's tanks appear ready to roll into gaza, and the skies have been raining rockets there for several days. perhaps the larger worry, both sides in this escalating fight have powerful friends that are getting involved and taking sides, like egypt, friend of hamas, and the united states, which tonight is sending naval vessels offshore in case americans need to get out of there. it has been another day of explosions and air raid sirens. it remains a situation on the edge. we have two reports tonight. our richard engel is in gaza, we want to begin, though, with martin fletcher in tel aviv. >> reporter: good evening, they met on the agenda escalating in gaza and a possible ground invasion.